Valve for pressurized liquid dispenser

ABSTRACT

A valve assembly for aerosol dispensers having, in an apertured valve socket of a pressurized aerosol container, a valve seat of resilient material such as rubber with an aperture in registry with that of the valve socket; a substantially rigid valve disc of which the the upper surface forms a seal when in contact with the valve seat, having a tubular stem integral with the disc and extending through its aperture, adapted to receive a conventional spray nozzle on its outer end-the bore of the stem terminating at the valve disc and communicating with one or more radial ports normally closed by contact with the inner surface of the bore through the valve seat; and a valve housing of substantially rigid material, clamped by appropriate crimping or the like of the side walls of the valve socket against the edges of the valve seat to form a seal therewith, said housing having an inner chamber of somewhat smaller cross section than the valve disc with a connection at its lower end for a dip tube extending to the base of the container, and a counterbore adjacent the valve disc and large enough to receive the latter, the base of the counterbore having a fulcrum support normally holding the valve disc against the valve seat and located within the limit of peripheral contact of the disc with the valve seat, and a cutaway portion-such as a plane surface inclined to and intersecting the axis of the valve stem and extending from said fulcrum support to the opposite side of the valve housing, into which the valve disc may tilt by rotation about the fulcrum support to open a passage from the interior of the valve housing between the disc and valve seat to a radial port at the base of the valve stem, through which the pressurized contents of the container are released through the dip tube, valve housing, valve stem and nozzle; and resilient means- either the resilient valve seat on the side of the fulcrum support opposite said cut-away portion if said support is spaced inwardly from the limit of peripheral contact of the disc and valve seat (such that tilting of the disc about the fulcrum support toward the cut-away portion of the valve housing compresses the valve seat on the opposite side of said support), and/or a resiliently flexible leg extending downward from one side of the valve disc with its outer end bearing upon the cut-away portion of the base of the valve housing counterbore (especially when the said cut-away portion has a plane surface inclined to the axis of the valve stem axis)such resilient means urging the valve disc when displaced by tilting of the valve stem and disc around the fulcrum support to contents-releasing position to return the same to sealing contact with the valve seat. When such a resiliently flexible leg is provided, the fulcrum support can be located at the peripheral limit of contact of the valve disc with the valve seat.

United States Patent 1 Harris 451 Jan. 2, 1973 [76] Inventor: Arthur M.Harris, 135 Southwood Road, Fairfield, Conn. 06430 [22] Filed: May21,1970

[21] Appl.No.: 39,399

Primary Examine rRobert B. Reeves Assistant Examiner-Norman L. Stack,Jr. Attorney-Walter G. Hensel [57] ABSTRACT A valve assembly for aerosoldispensers having, in an apertured valve socket of a pressurized aerosolcontainer, a valve seat of resilient material such as rubber with anaperture in registry with that of the valve socket; a substantiallyrigid valve disc of which the the upper surface forms a-seal when incontact with the valve seat, having a tubular stem integral with thedisc and extending through its aperture, adapted to receive aconventional spray nozzle on its outer end--the bore of the stemterminating at the valve disc and communicatingwith-one or more radialports normally closed by contact with the inner surface of the borethrough the valve seat; and a valve housing of substantially rigidmaterial, clamped by appropriate crimping or the like of the side wallsof the valve socket against'the edges of the valve seat to form a sealtherewith, said housing having an inner chamber of somewhat smallercross section than the valve disc with a connection at its lower end fora dip tube extending to the base of the container, and a counterboreadjacent the valve disc and large enough to receive the latter, the baseof the counterbore having a fulcrum support normally holding the valvedisc against the valve seat and located within the limit of peripheralcontact of the disc with the valve seat, and a cut-away portionsuch as aplane surface inclined to and. intersecting the axis of the valve stemand extending from said fulcrum support to the opposite side of thevalve housing, into which the valve disc may tilt by rotation about thefulcrum support to open a passage from the interior of the valve housingbetween the disc and valve seat to a radial port at the base of thevalve stem, through which the pressurized contents of the container arereleased through the dip tube, valve housing, valve stem and nozzle; andresilient means-either the resilient valve seat on the side of thefulcrum support opposite said cut-away portion if said support is spacedinwardly from the limit of peripheral contact 0 the disc and valve seat(such tha tilting of the disc about the fulcrum support toward thecut-away portion of the valve housing compresses the valve seat on theopposite side of said support), and/or a resiliently flexible legextending downward from one side of the valve disc with its outer endbearing upon the cutaway portion of the base of the valve housingcounterfulcrum support can be located at the peripheral limit a ofcontact of the valve disc with the valve seat.

8 Claims, 6 Drawing Figures SHEEI 1 0F 2 FIG. 1

INVENTOR. ARTHUR M. HARRIS ATTORNEY PATENTED JAN 2 1973 3. 708. 09 OSHEET 2 OF 2 INVENTOR. ARTHUR M. HARRIS AT TORNEY VALVE roupnassuiuzs'n-uoum nisrsssan disc-the counterbore forming a continuationof larger cross sectional size of the inner chamber or borementionedabove.

In accordance with this'invention, the base of the counterbore includesa fulcrum support (e.g., a line or point or series of points) insupporting contact with the lower face of the valve discso as-to holdthe same normally in sealing contact with the resilient valve seat, anda cut-away portion having asurface extending at least from said fulcrumsupport away from the valve disc to the opposite side of the valvehousingsaid cutaway portion being advantageously constituted by aFurther, it is desirable to provide a valve assembly assuring reliableoperation for release of the pressurized liquid, and reliable closure toprevent leakage when the release operation is terminated.

It is an object of this invention to provide a valve assembly affordingeach of the aforesaid desiderata, and susceptible of constructionandoperation without the necessity of metal springs, affording reliabilityin ope'rasimplicity and economy in manufaction and" utmost Other objectsand advantageswill be apparent to those skilled in the art from thefollowing description of the invention, and from the specific.embodiments thereof hereinafter described with reference to theaccornpanying'drawings. 1 i J in accordance with this invention, thereis provided a valve assembly, adapted to be fastened 'inja'centrallyape'rtured valve'socket of acontainer for pressurized liquids suchasaerosols, comprising ai valve seat of resilient material such asrubber or similar'synthetic elastomers, mounted against the inside endwall of the socket and having an aperture no larger than the aper: tureof the socket and in registry therewith. The valve assembly furtherincludes a substantially rigid valve I member or disc, having anupper'surface' shaped to form a seal with ,the'lower surface of thevalve seat when in contact therewith circumferentially of the aperturetherein, and a tubular jvalvestemintegral V with ,the valve discextending outward therefrom more lateral (radial) ports which arenormally sealed by the wall of the valve seat aperture when the valveseat is in sealing contact with thevalve disc.

Further, the valve assembly of my invention includes a valve housing ofsubstantially rigid material, mounted in the valve socket of thecontainer against the valve seat; The housinghas an interiorchamber orbore, somewhat smaller in cross section than the valvefldisc,

having a tubular extension atits lower end, adapted to be connected to aconventional dip; tube extending towardthe'base of the container withits lowerend immersed in the pressurized liquid contained therein. The

upper end of the housing is providedlwith an externalv annular flange ofabout the same extemal' size and shape as the valve seat, clampedagainst the outer edge portion-of the latter in sealing contactbyasupporting annular shoulder formed e.g. by crimping, in the wall ofthe valve socket. At its upper end, oppositesaidtubular connection,:thevalve housing' is provided with a counterboreof such size and shape astoreceive the valve plane surface intersecting and inclined to the axis ofthe valve stem and extending from the fulcrum support to v the oppositeside of the valvehousing counterbore.

When the fulcrum support is located at the axis of the valve disc andstem, or intermediate said axis and the peripheral limit of contact ofthe valve disc with the valve seat, but inwardly spaced from said limit,the resilient valve seat on opposite sides of the fulcrum support exertsresilient pressure on the valve disc, resisting itsdisplacernent aroundthefulcrum, and thus tends to retain the valve discin sealingcontac'twith the valve seat. Said resilient force may be advantageouslysupplemented by a resiliently flexible leg, integral with and extendingdownward from one side of the'valve disc such that its lower end issupported on the cut-away surface-especially, a plane surface inclinedto the axis .of the valvedisc and stem-its length being such as to withthe valve seat, rather than inwardly"spaced therefrom, then aflexibleleg: as justdescribed cooperates on its sideof thefvalve discwith thefulcrum support on the opposite side to hold: the valve disc resilientlyin sealing contact with the valve seat. 1 7 Once sealing contact ofthevalve disc with the resilient 'valve'seatis established, thefluidpressure within the pressurized container supplements the resilientpressures above described to hold the valve disc against the valve seat,thepressurized contents. V

Operation of the valve assembly of this invention to releasethepressurized contents of the container involves tilting of thevalve'stem and its integral valve thus" preventing escape of disc bylateral and downward manual'forceusually applied tothe spray nozzle onthe outer end of the stem,

whereby the valve disc is rotated about the fulcrum support on the baseof the valve housingcount erbore the side of the valve disc toward whichthey tilting force is applied being tilted downwardtowardthe cutawayportion of the counterbore ,',especially"tlie plane surface inclined tothe *axis of the valve stem in its originalsposition the downwardlydisplaced portion ofthe valve disc thereby moving out of contactwith-its side of the valve seat, and a radial port at the base of thevalve stem moving out of .contactwith the wall of the valve seatbore,thusopening a passage from the interior of the valve housing tothe valvestem bore and releasing the pressurized contents of the container whichpass through the dip tubeintothe valve housing, thence through thepassage and port just described, and then through the valve stem bore tothe spray nozzle.

Tilting of the valve disc ab'out its fulcrumlsupportvv causes that sideof the disc opposite the depressed side to tilt upward againsttheresilient pressure of the valve seat and/or causes the resilientlyflexible leg on the depressed side of the valve disc to flex, especiallyto flex outward from the valve disc axis while its outer end slidesdownward along the inclined plane surface of the cut-away portion of thebase of the valve housing counterbore. The flexed leg and/or thecompressed portion of the resilient valve seat resiliently urge thevalve disc around the fulcrum support to return to sealing contact withthe valve'seat, and this occurs when the manual tilting force isreleased, thus stopping release of the pressurized contents of thecontainer.

Specific embodiments of my invention are illustrated in the accompanyingdrawings, wherein FIG. 1 is a side view mainly in axial cross section ofa valve assembly in accordance with my invention, mounted in the valvesocket of an aerosol dispenser (of which only the upper part isillustrated) provided with a conventional spray nozzle and dip tube(part of which is shown).

FIG. 2 is a view similar to FIG. 1, but showing the valve assembly incontents-releasing position.

FIG. 3 is also similar to FIG. 1, but illustrates a modified form ofvalve disc.

FIG. 4 illustrates the valve assembly in FIG. 2 in contents-releasingposition.

FIG. 5 is similar to FIG. 1, but illustrates provision of a fulcrumsupport on the base of the valve housing at the limit of peripheralcontact of the valve disc with the resilient seat.

FIG. 6 illustrates the valve assembly of FIG. 3 in contents-releasingposition.

, As shown in FIG. 1, a valve assembly in accordance with my inventionis shown mounted in the valve socket at the top of a pressurized aerosolcontainer 10 of sheet metal or other pressure-resistant material, and ofconventional cylindrical shape. The generally flat upper surface 11 ofthe socket is centrally apertured at 12 to accommodate a valve stem 13extending upward through the aperture, and a crimped portion spaceddownward from the top 11 provides an annular shoulder 14 clamped againstand supporting an external annular flange 15 at the upper end of valvehousing 16 in sealing contact with the periphery of a centrallyapertured resilient valve seat 17, which is in turn peripherally clampedbetween flange l5 and top 11 of the valve socket in sealing contact withthe latter. The valve stem 13 (which is provided at its outer end with aspray nozzle of conventional design for aerosol dispensers) is integralwith a valve disc 18 to which it is centrally joined by a portion 19 ofreduced diameter corresponding to that of the central aperture of thevalve seat 17, and of the same length as the thickness of the valveseat, so as to provide an annular groove at the base of the valve stemto receive the inner edge of the valve seat aperture. The central bore20 of valve stem 13 terminates adjacent valve disc 18 in a series ofradial ports 21 extending outward to the surface of annular groove 19.

The valve housing 16 has an internal chamber formed by a bore 22 of adiameter somewhat smaller then that of valve disc 18, extending downwardto communicate with a nipple23 to which is connected a dip tube 24extending downward to a point adjacent the base of the container 10where it is immersed in the pressurized liquid to be dispensed.Optionally, the wall of the chamber 22 may be provided with a cappillaryopening 25 affording limited access to said chamber of the pressurizedvapor phase within the container 10. In this way, the pressurizedcontents released from the chamber 22 through the valve stem 13 and itsterminal spray nozzle are diluted by the simultaneously released vaporphase entering the chamber 22 through the capillary opening 25. I

The upper end of the valve housing 16 has a counterbore 26 of slightlylarger diameter than the valve disc 18 and of such depth at one side asto provide a shoulder 27 supporting the valve disc 18 in sealing contactwith the valve seat 17, but terminating at a fulcrum point 28intermediate the axis of the valve disc 18 and its periphery, saidfulcrum point being spaced inward from the latter. From the fulcrumpoint 28, the base of the counterbore 26 slopes downward at an acuteangle with the valve stem axis. The fulcrum 28, being within theperiphery of the valve disc 18, normally supports the latter in sealingcontact with the resiliently yielding valve seat 17 which provides aresilient forcepreventing access of the pressurized contents of thecontainer 10 to ports 21 and bore 20 of valve stem 13.

When the stem 13 is subjected to downward manual force applied to itsterminal spray nozzle, it tilts the valve disc 18 about the fulcrumpoint 28 (as shown in FIG.'1A) toward the downwardly sloping base 29 ofcounterbor'e 26 and correspondingly away from that side of the valveseat 18, opening a passage 30 from the interior of the valve housing tothe aperture of the valve seat 18. At the same time, such tilting causesthe annular grooved portion 19 of the valve stem to cam the lower edgeof the valve seat aperture downward and out of contact with said annulargroove 19 of the valve stem, thus opening passage 30 to a port 21 ot thevalve stem. So long as the valve disc 18 is held in this position, thepressurized liquid contents of the container 10 is forced upward throughthe dip tube 24 through the chamber 22 of the valve housing, passage 30,port 21 and valve stem bore 20 to the spray nozzle on the outer end ofthe valve stem. There, it is emitted in the form of a spray, admixedwith such portion of the pressurized vapor phase of the contents ofcontainer 10 as is admitted to chamber 22 through capillary opening 25.

When the aforesaid manual tilting force is released, the resilient forceapplied by the compressed portion of valve seat 17 against upwardlydisplaced portion of valve disc 18 to the right (in FIG. 1 and 2) of thefulcrum point 28, moves the disc 18 clockwise around the fulcrum point,bringing the left hand side of the valve disc 18 into sealing contactwith the valve seat 17 and at the same time, returning port 21 tosealing contact with the adjacent inner surface of the aperture of thevalve seat 17. Once such sealing contact is reestablished between thevalve disc 18 and valve seat 17, the interior pressure within thecontainer 10 holds the disc 18 against the valve seat 17, preventingescape of the pressurized contents of container 10 until the nextspraying operation.

FIGS. 3 and 4 show a modification of the valve assembly of FIGS. 1 and1A, wherein the valve disc 18' is provided with a resiliently flexibleleg 31, extending downward therefrom on the side opposite fulcrum 28,

into contact with sloping surface 29 of counterbore 26, and providingsupplementary support to hold valve disc 18' in contact with valve seat17. When valve stem 13' is tilted (as shown in FIG. 4), the leg 31flexes outward as its tip slides along the downwardly sloping surface 29of the base of counterbore 26, and on release of the stem-tilting force,resiliently urges its side of the valve disc 18' into contact with valveseat 17. The flexed stem, cooperating with sloping surface 29 of thecounterbore 26, thus supplements the resilient force of the compressedportion of valve seat 17 on the opposite side of fulcrum point 28.

FIGS. 5 and 6 show a still further modification of the valve assemblyaccording to my invention, wherein, as distinguished from theconstruction shown in FIGS. 1 and 2, the fulcrum point 28" is located atthe limit of peripheral contact of the valve disc 18' with the valveseat 17. In this case, the fulcrum point 28" supports the edge of thevalve disc 18' in contact with the valve seat 17, but no compression ofthe valve seat 17 occurs adjacent the fulcrum point when the valve stem13" is tilted to spraying position as shown in FIG. 6. However, theresiliently flexible leg 31' extending downward from disc 18' oppositefulcrum point '28.", having flexed outward through contact with slopingsurface 29" of counterbore 26" of the valve housing exerts a resilientforce urging disc 18' clockwise about fulcrum point 28", returning thesame to scaling contact with valve seat 17 when the manual tilting forceapplied to the valve stem 13' is released.

As will be obvious to those skilled in the art, the fulcrum point 28 ofFIGS. 1 and 3 can be located at any point from the valve stem axis to apoint spaced inwardly from the limit of peripheral contact of the valvedisc with the valve seat the location of said fulcrum point at the limitof said periphery (or beyond the same), as shown in FIG. 5, requiringmerely a supplementary resilient support, such as that afforded byresiliently flexible leg 31' of which the lower end is supported on thesloping surface 29" of the base of coun- 'terbore 26" of the valvehousing. a

6 parts are, for example, polyethylene, polystyrene,p'olymethyltnethacrylate, cellulose esters and similar plastics,selected in each case to be inert toward the intended contents of thepressurized container. The valve seat is made of resilientlyyieldingsealing material such as rubber, or synthetic elastomers such asbutadiene polymers, chloroprene Buna S or GRS rubber. Again,

the material chosen should be inert (i.e. against chemi cal reaction,swelling or dissolution) toward the liquid contents of the pressurizedcontainer.

It will be observed that my valve assembly consists of I but threeessential parts for mounting in the valve socket of a pressurizedcontainer, namely, a valve seat, a valve disc and integral valve stemand a valvehousing, each of which can be readily molded by conventionalprocedures from conventional plastics. No metal parts are required, andthe assembly of the parts is extremely simple, involving merelythreading the valve stem through the apertured valve seat, mountingthese parts in the valve socket of the container, inserting thepolyfluoroor polyfluoropoly-chloro derivatives of In each of the valveassemblies illustrated in the the inner surface of the valve seataperture provides a closure for the radial port or ports 21 on the sideor rear of the valve stem opposite the port. 21 which is openedbytilting of the valve stem on the side toward which tilting occurs.

The container 10, conventionally of sheet metal, can be made of anyother pressure-resistant sheet material which is substantially inerttoward the liquid contents of the container e.g. of polyethylene,polystyrene, cellulose esters or'thelike. The valve stem and disc andthe .valve housing are appropriately made of substantially rigidplastic, which, in a relatively thin layer as provided in the leg 31 or31', is sufficiently flexible to bend resiliently in response to tiltingforce applied to the valve disc and stem. Suitable materials for theselower aliphatic hydrocarbons. The vapor pressure of the propellantmaintains the container contents under pressure. When the pressurizedcontents are released by operation of the valve assembly of thisinvention, the propellant vaporizes and the non-volatile componentto besprayed is emmitted in atomized form from the spray nozzle at the top ofthe valve stem.

Variations and modifications which will be obvious to those skilledinthe art cari be made in the foregoing specificembodiments of myinvention without departing from the scope or spirit thereof.

' I claim l. A valve assembly for apressurized container comprising incombination:

a. an annular valve seat of resiliently yielding materia b. a valve dischaving an upper surface engageable and adapted to form a seal with saidseat,

- c. a tubular valve stem on said valve disc, extending through thevalve. seat, the bore of said stem terminating at the valve disc andcommunicating at said terminal with at leastone lateral port,

'd. and a valve housing secured at its upper end in sealing contact withsaid valve seat and connected at its lower end with a dip tube, saidhousing having a shoulder engaging the lower surface of said valve discat a peripheral portion of the disc and constituting a fulcrum supporttherefor to position said valve disc against said valve seat, saidshoulder sloping away from said valve disc, tilting of said valve discdownward about said fulcrum I support opening a passage for the contentsof said pressurized container from the interior of said valve housingbetween said valve disc and valve seat to at least one of said lateralports at the base of said valve stem, and thence to the central bore ofthe latter, and

e. said valve assembly further including means normally urging saidvalve disc upward about said fulcrum support into contact with the undersurface of said valve seat.

2. A valve assembly as defined in claim 1 wherein said fulcrum supportis located within the range from the axis of said valve stem to a pointwithin but spaced from the periphery of said valve seat.

3. A valve assembly as defined in claim 2 wherein the surface of saidshoulder adjacent to said fulcrum support clamps said valve disc againstsaid valve seat.

4. A valve assembly as defined in claim '2 wherein compression of saidvalve seat by said valve disc when the latter is tilted exerts forceagainst said disc which tends to return the disc.

5. A valve assembly as defined in claim 1 wherein said shoulder of saidvalve housing has a substantially plane surface, inclined to andintersecting the axis of said valve stem.

6. A valve assembly as defined in claim 5, wherein said meansresiliently urging said valve disc about its fulcrum support comprises aresiliently flexible leg integral withsaid valve disc, having its outerend supported on the shoulder in the housing.

7. A valve assembly as defined in claim 6 wherein said fulcrum supportis located at the limit of peripheral contact of said valve disc withsaid valve seat.

8. A valve assembly for a pressurized container, comprising incombination:

a. an annular valve seat of resiliently yielding materia valve discmember having an upper surface engageable and adapted to form a sealwith said valve seat,

. a tubular valve stem on said valve disc member,

extending through the valve seat, the bore of said stem terminating atthe valve disc member and communicating at said terminal with at leastone lateral port,

. and a valve housing member secured at its upper end insealing contactwith said valve seat and connected at its lower end with a dip tube,said housing member having a shoulder engageable with the under side ofsaid valve disc member at a peripheral portion of the disc andconstituting a fulcrum support therefor to position said valve disc saidvalve assembly further including means normally urging said valve discmember upward about said fulcrum support into contact with the undersurface of said valve seat, one of said members having a resilientlyflexible leg extending th refrom, the terminus of said leg enga ing theot er part, said leg constituting said means 0 normally urging the valvedisc member upward.

. s it

1. A valve assembly for a pressurized container comprising incombination: a. an annular valve seat of resiliently yielding material,b. a valve disc having an upper surface engageable and adapted to form aseal with said seat, c. a tubular valve stem on said valve disc,extending through the valve seat, the bore of said stem terminating atthe valve disc and communicating at said terminal with at least onelateral port, d. and a valve housing secured at its upper end in sealingcontact with said valve seat and connected at its lower end with a diptube, said housing having a shoulder engaging the lower surface of saidvalve disc at a peripheral portion of the disc and constituting afulcrum support therefor to position said valve disc against said valveseat, said shoulder sloping away from said valve disc, tilting of saidvalve disc downward about said fulcrum support opening a passage for thecontents of said pressurized container from the interior of said valvehousing between said valve disc and valve seat to at least one of saidlateral ports at the base of said valve stem, and thence to the Centralbore of the latter, and e. said valve assembly further including meansnormally urging said valve disc upward about said fulcrum support intocontact with the under surface of said valve seat.
 2. A valve assemblyas defined in claim 1 wherein said fulcrum support is located within therange from the axis of said valve stem to a point within but spaced fromthe periphery of said valve seat.
 3. A valve assembly as defined inclaim 2 wherein the surface of said shoulder adjacent to said fulcrumsupport clamps said valve disc against said valve seat.
 4. A valveassembly as defined in claim 2 wherein compression of said valve seat bysaid valve disc when the latter is tilted exerts force against said discwhich tends to return the disc.
 5. A valve assembly as defined in claim1 wherein said shoulder of said valve housing has a substantially planesurface, inclined to and intersecting the axis of said valve stem.
 6. Avalve assembly as defined in claim 5, wherein said means resilientlyurging said valve disc about its fulcrum support comprises a resilientlyflexible leg integral with said valve disc, having its outer endsupported on the shoulder in the housing.
 7. A valve assembly as definedin claim 6 wherein said fulcrum support is located at the limit ofperipheral contact of said valve disc with said valve seat.
 8. A valveassembly for a pressurized container, comprising in combination: a. anannular valve seat of resiliently yielding material, b. a valve discmember having an upper surface engageable and adapted to form a sealwith said valve seat, c. a tubular valve stem on said valve disc member,extending through the valve seat, the bore of said stem terminating atthe valve disc member and communicating at said terminal with at leastone lateral port, d. and a valve housing member secured at its upper endin sealing contact with said valve seat and connected at its lower endwith a dip tube, said housing member having a shoulder engageable withthe under side of said valve disc member at a peripheral portion of thedisc and constituting a fulcrum support therefor to position said valvedisc member against said valve seat, said shoulder 70 away from saidvalve disc member, tilting of said valve disc member downward about saidfulcrum support opening a passage for the contents of said pressurizedcontainer from the interior of said valve housing member between saidvalve disc member and valve seat to at least one of said lateral portsat the base of said valve stem, and thence to the central bore of thelatter, and e. said valve assembly further including means normallyurging said valve disc member upward about said fulcrum support intocontact with the under surface of said valve seat, one of said membershaving a resiliently flexible leg extending therefrom, the terminus ofsaid leg engaging the other part, said leg constituting said means fornormally urging the valve disc member upward.